"I have pledged my full cooperation to the Company, and I have the utmost confidence in our CEO, Victor Herrero, to continue leading the Company during this time," Marciano, who has denied the claims, said in a statement on Tuesday.

"The Board of Directors and Mr. Marciano have agreed that Mr. Marciano will relinquish his day to day responsibilities at the Company, on an unpaid basis, pending the completion of the investigation," a statement from Guess reads. "The Company takes very seriously any allegations of sexual misconduct, is committed to maintaining a safe work environment, and looks forward to the completion of a thorough investigation of all the facts."

"It's disappointing that such an iconic women's brand @GUESS is still empowering Paul Marciano as their creative director #metoo," Upton, who has modeled for the brand in the past, tweeted.

A week later, Upton detailed the alleged misconduct in an interview with Time.

"After the first day of shooting the Guess Lingerie campaign [on July 25, 2010], Paul Marciano said he wanted to meet with me. As soon as I walked in with photographer Yu Tsai, Paul came straight up to me, forcibly grabbed my breasts and started feeling them — playing with them actually. After I pushed him away, he said, 'I'm making sure they're real,'" Upton told the publication. "Despite doing everything I could physically do to avoid his touch throughout the meeting, he continued to touch me in a very dominating and aggressive way, grabbing my thighs, my arms to pull me closer, my shoulders to pull me closer, my neck, my breasts, and smelling me. He then told Yu Tsai to leave us alone."

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Upton went on to allege that on her next shoot with Guess a month later, company co-founder Marciano called her asking to see her hotel room, which she told the publication she declined multiple times.

"The next day, I learned that I had been fired from the shoot. Someone had called my agency to say I had gotten fat and would not be needed on set [that day]," Upton claimed. "I was devastated, especially because at this point no one from Guess had even seen me."

She went on to tell of her final Guess shoot, "I had a final shoot [in May of 2011], and he was outwardly rude and degrading the entire time. He said I was 'disgusting' and started telling people how unprofessional I was by spreading rumors that I was drunk on set and partying every night, which of course I wasn't," Upton claimed. "I was then told to leave because Paul had said, 'Get that fat pig off my set.'"

Upton told Time she came forward because, "Paul used his power to make me feel insecure and powerless, but I'm not going to let him intimidate me anymore. These men think they are untouchable, but times are changing."

In response to Upton's allegations, Marciano told Time, "I have never been alone with Kate Upton. I have never touched her inappropriately. Nor would I ever refer to a Guess model in such a derogatory manner. I fully support the #metoo movement. At the same time, I will not allow others to defame me and tarnish my reputation. I have pledged to Guess and its Board of Directors my full support and cooperation with a fair and impartial investigation."

Following Upton's tweet on January 31, Marciano also denied her claims to TMZ.

"If she has a claim, there's one place to tell the truth and that's in court or to the police," Marciano said.